Enable eventlet dependency on Python 3

Bump eventlet to 0.17.3, the first release fully supporting Python 3
with monkey-patching.

Add aioeventlet and trollius dependencies for the aioeventlet
executor on Python 3.

This change enables tests of eventlet and aioeventlet executors on
Python 3.

Add futures to Python 3 dependencies even if it's not needed, it's
required to workaround a bug in tox.

Depends-on: I73e3056b5e8b9ce710c9c2d59fc5be8e03e28d2a
Change-Id: I0efae1c91c5d830156b867d7d21b5c0065094665

requirements-py3.txt

@@ -12,6 +12,11 @@ stevedore>=1.3.0  # Apache-2.0
 # for jsonutils
 six>=1.9.0
 
+# FIXME(markmc): remove this when the drivers no longer
+# import eventlet
+
+eventlet>=0.17.3
+
 # for the routing notifier
 PyYAML>=3.1.0
 
@@ -20,3 +25,19 @@ kombu>=2.5.0
 
 # middleware
 oslo.middleware>=1.0.0                  # Apache-2.0
+
+# FIXME: concurrent.futures is part of the Python stdlib since Python 3.2,
+# but the requirements is still needed because of a bug in tox:
+# https://bitbucket.org/hpk42/tox/issue/236/tox-must-create-the-source-distribution
+#
+# Tox builds a source distribution with "python setup.py sdist" which uses
+# requirements.txt even if tox wants to build the py34 virtual environment.
+# As a consequence, oslo.messaging.egg_info/requires.txt contains futures
+# and oslo_messaging.tests.test_opts.OptsTestCase.test_entry_point fails.
+#
+# for the futures based executor
+futures>=2.1.6
+
+# needed by the aioeventlet executor
+aioeventlet>=0.4
+trollius>=1.0

requirements.txt

@@ -17,7 +17,7 @@ six>=1.9.0
 # FIXME(markmc): remove this when the drivers no longer
 # import eventlet
 
-eventlet>=0.16.1,!=0.17.0
+eventlet>=0.17.3
 
 # for the routing notifier
 PyYAML>=3.1.0